title: Validity of diagnostic codes to identify cases of severe acute liver injury in the US Food and Drug Administration's Mini-Sentinel Distributed Database.
abstract: OBJECTIVE
  The validity of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes to identify diagnoses of severe acute liver injury (SALI) is not well known. We examined the positive predictive values (PPVs) of hospital ICD-9-CM diagnoses in identifying SALI among health plan members in the Mini-Sentinel Distributed Database (MSDD) for patients without liver/biliary disease and for those with chronic liver disease (CLD).
  
  
  METHODS
  We selected random samples of members (149 without liver/biliary disease; 75 with CLD) with a principal hospital diagnosis suggestive of SALI (ICD-9-CM 570, 572.2, 572.4, 572.8, 573.3, 573.8, or V42.7) in the MSDD (2009-2010). Medical records were reviewed by hepatologists to confirm SALI events. PPVs of codes and code combinations for confirmed SALI were determined by CLD status.
  
  
  RESULTS
  Among 105 members with available records and no liver/biliary disease, SALI was confirmed in 26 (PPV, 24.7%; 95%CI, 16.9-34.1%). Combined hospital diagnoses of acute hepatic necrosis (570) and liver disease sequelae (572.8) had high PPV (100%; 95%CI, 59.0-100%) and identified 7/26 (26.9%) events. Among 46 CLD members with available records, SALI was confirmed in 19 (PPV, 41.3%; 95%CI, 27.0-56.8%). Acute hepatic necrosis (570) or hepatorenal syndrome (572.4) plus any other SALI code had a PPV of 83.3% (95%CI, 51.6-97.9%) and identified 10/19 (52.6%) events.
  
  
  CONCLUSIONS
  Most individual hospital ICD-9-CM diagnoses had low PPV for confirmed SALI events. Select code combinations had high PPV but did not capture all events.
authors.affiliation: Division of Infectious Diseases, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. vincentl@mail.med.upenn.edu
authors.forename: Vincent
authors.initials: V
authors.lastname: Lo Re
authors.forename: Kevin
authors.initials: K
authors.lastname: Haynes
authors.forename: David
authors.initials: D
authors.lastname: Goldberg
authors.forename: Kimberly A
authors.initials: KA
authors.lastname: Forde
authors.forename: Dena M
authors.initials: DM
authors.lastname: Carbonari
authors.forename: Kimberly B F
authors.initials: KB
authors.lastname: Leidl
authors.forename: Sean
authors.initials: S
authors.lastname: Hennessy
authors.forename: K Rajender
authors.initials: KR
authors.lastname: Reddy
authors.forename: Pamala A
authors.initials: PA
authors.lastname: Pawloski
authors.forename: Gregory W
authors.initials: GW
authors.lastname: Daniel
authors.forename: T Craig
authors.initials: TC
authors.lastname: Cheetham
authors.forename: Aarthi
authors.initials: A
authors.lastname: Iyer
authors.forename: Kara O
authors.initials: KO
authors.lastname: Coughlin
authors.forename: Sengwee
authors.initials: S
authors.lastname: Toh
authors.forename: Denise M
authors.initials: DM
authors.lastname: Boudreau
authors.forename: Nandini
authors.initials: N
authors.lastname: Selvam
authors.forename: William O
authors.initials: WO
authors.lastname: Cooper
authors.forename: Mano S
authors.initials: MS
authors.lastname: Selvan
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: VanWormer
authors.forename: Mark I
authors.initials: MI
authors.lastname: Avigan
authors.forename: Monika
authors.initials: M
authors.lastname: Houstoun
authors.forename: Gwen L
authors.initials: GL
authors.lastname: Zornberg
authors.forename: Judith A
authors.initials: JA
authors.lastname: Racoosin
authors.forename: Azadeh
authors.initials: A
authors.lastname: Shoaibi
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D056486:Chemical and Drug Induced Liver Injury / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D002908:Chronic Disease; D059019:Clinical Coding; D003430:Cross-Sectional Studies; D016208:Databases, Factual / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D038801:International Classification of Diseases; D008107:Liver Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D008297:Male; D008499:Medical Records / Q000706:statistics & numerical data; D008875:Middle Aged; D017891:Pharmacoepidemiology; D011237:Predictive Value of Tests; D011358:Product Surveillance, Postmarketing; D012720:Severity of Illness Index; D014481:United States / Q000453:epidemiology; D014486:United States Food and Drug Administration
keywords: ICD-9 codes; hepatotoxicity; liver injury; pharmacoepidemiology; validity